1000+ Concrete Technology and Design Multiple Choice Question Answer [Solved]

1. The temperature reinforcement in the vertical slab of a T-shaped R.C. retaining wall is
A. Not needed
B. Provided equally on inner and front faces
C. Provided more on inner face than on front face
D. Provided more on front face than on inner face
Answer : D

2. After casting, an ordinary cement concrete on drying
A. Expands
B. Mix
C. Shrinks
D. None of these
Answer : C

3. Minimum grade of concrete to be used in reinforced concrete as per IS: 4561978 is
A. M 15
B. M 20
C. M 10
D. M 25
Answer : A

4. Separation of water or water sand cement from a freshly concrete, is known
A. Bleeding
B. Creeping
C. Segregation
D. Flooding
Answer : A

5. For a concrete mix 1:3:6 and water cement ratio 0.6 both by weight, the quantity of water required per bag, is
A. 10 kg
B. 12 kg
C. 14 kg
D. 16 kg
Answer : C

6. Select the incorrect statement
A. The loss of pre-stress is more in pre-tensioning system than in posttensioning system.
B. Pre-tensioning system has greater certainty about its durability.
C. For heavy loads and large spans in buildings or bridges, posttensioning system is cheaper than pre-tensioning system
D. None of the above
Answer : D

7. The compaction of concrete, improves
A. Density
B. Strength
C. Durability
D. All the above
Answer : D

8. In slump test, each layer of concrete is compacted by a steel rod 60 cm long and of 16 mm diameter for
A. 20 times
B. 25 times
C. 30 times
D. 50 times
Answer : B

9. For the construction of cement concrete dams, the maximum permissible size of the aggregates, is
A. 40 mm
B. 50 mm
C. 60 mm
D. 70 mm
Answer : A

10. Sand generally contains salt if it is obtained from:
A. Nala beds
B. River beds
C. Sea beds
D. None of these
Answer : C

11. If the size of panel in a flat slab is 6 m × 6 m, then as per Indian Standard Code, the widths of column strip and middle strip are
A. 3.0 m and 1.5 m
B. 1.5 m and 3.0 m
C. 3.0 m and 3.0 m
D. 1.5 m and 1.5 m
Answer : C

12. For preparing a test-specimen, it is necessary
A. To mix cement and fine aggregate by dry hand
B. To mix coarse aggregates
C. To mix water to the cement, fine aggregates and coarse aggregates
D. All the above
Answer : D

13. The commercial name of white and coloured cement in India, is
A. Colorcrete
B. Silvicrete
C. Snowcem
D. All the above
Answer : D

14. Sands of zone I are:
A. Course
B. Medium
C. Medium to fine
D. Fine
Answer : A

15. The void ratio of
A. Single size coarse aggregate is roughly 0.45
B. Graded coarse aggregate is roughly 0.040
C. Fine aggregate is roughly 0.45
D. All the above
Answer : D

16. Curing of pavements, floors, roofs and slabs, is done by
A. Membrane method
B. Ponding method
C. Covering surface with bags
D. Sprinkling water method
Answer : B

17. The design yield stress of steel according to IS: 4561978 is: (Where f_y is the characteristic yield strength of steel)
A. 0.37 f_y
B. 0.57 f_y
C. 0.67 f_y
D. 0.87 f_y
Answer : D

18. For walls, columns and vertical faces of all structural members, the form work is generally removed after
A. 24 to 48 hours
B. 3 days
C. 7 days
D. 14 days
Answer : A

19. According to I.S. : 456, the number of grades of concrete mixes, is
A. 3
B. 4
C. 5
D. 7
Answer : D

20. The rock which is not calcareous, is:
A. Lime stone
B. Chalk
C. Laterite
D. None of these
Answer : D

21. Workability improved by adding
A. Air-entraining agent
B. Foaming agent
C. Oily-agent
D. All the above
Answer : D

22. Minimum pitch of transverse reinforcement in a column is
A. The least lateral dimension of the member
B. Sixteen times the smallest diameter of longitudinal reinforcement bar to be tied
C. Forty-eight times the diameter of transverse reinforcement
D. Lesser of the above three values
Answer : D

23. The most useless aggregate is one whose surface texture is
A. Smooth
B. Granular
C. Glassy
D. Honey combed and porous
Answer : C

24. Sinking of an intermediate support of a continuous beam (i) Reduces the negative moment at support (ii) Increases the negative moment at support (iii) Reduces the positive moment at center of span (iv) Increases the positive moment at center of span The correct answer is
A. (i) and (iii)
B. (i) and (iv)
C. (ii) and (iii)
D. (ii) and (iv)
Answer : B

25. Slump test of concrete is a measure of its
A. Consistency
B. Compressive strength
C. Tensile strength
D. Impact value
Answer : A

26. Curing
A. Reduces the shrinkage of concrete
B. Preserves the properties of concrete
C. Prevents the loss of water by evaporation
D. All of the above
Answer : D

27. For batching 1:3:6 concrete mix by volume, the ingredients required per bag of 50 kg cement, are:
A. 70 litres of sand and 120 litres of aggregates
B. 70 kg of sand and 140 litres of aggregates
C. 105 litres of sand and 140 litres of aggregates
D. 105 litres of sand and 210 litres of aggregates
Answer : D

28. The 28 days cube strength of mass concrete using aggregates of maximum size 5 cm for gravity dams should be
A. Between 150 to 300 kg/cm²
B. Between 350 to 600 kg/cm²
C. Between 150 to 500 kg/cm²
D. Below 200 kg/cm²
Answer : D

29. Increase in the moisture content in concrete
A. Reduces the strength
B. Increases the strength
C. Does not change the strength
D. All of the above
Answer : A

30. Normally pre-stressing wires are arranged in the
A. Upper part of the beam
B. Lower part of the beam
C. Center
D. Anywhere
Answer : B

31. Pick up the incorrect statement from the following. While performing preliminary test on concrete
A. Proportions of the material and water should be the same as to be used at the work site
B. Cement should be mixed by hand in order to maintain uniformity
C. Concrete mix should be stored in air-tight containers
D. Concrete ingredients should be kept at a temperature of 37° ± 2°C
Answer : D

32. The process of proper and accurate measurement of concrete ingredients for uniformity of proportion, is known
A. Grading
B. Curing
C. Mixing
D. Batching
Answer : D

33. If 1500 g of water is required to have a cement paste 1875 g of normal consistency, the percentage of water is,
A. 20 %
B. 25 %
C. 30 %
D. 35 %
Answer : B

34. For compacting plain concrete road surface of thickness less than 20 cm, we use
A. Internal vibrator
B. Screed vibrator
C. Form vibrator
D. None of these
Answer : B

35. Maximum quantity of water needed per 50 kg of cement for M 15 grade of concrete is
A. 28 liters
B. 30 liters
C. 32 liters
D. 34 liters
Answer : C

36. A continuous beam is deemed to be a deep beam when the ratio of effective span to overall depth (1/D) is less than
A. 1.5
B. 2.0
C. 2.5
D. 3.0
Answer : C

37. Particles of 0.002 mm size are that of
A. Clay
B. Sand
C. Gravel
D. None of these
Answer : A

38. The final operation of finishing floors, is known as
A. Screeding
B. Floating
C. Trowelling
D. Finishing
Answer : C

39. The ratio of various ingredients (cement, sand, aggregates) in concrete of grade M 200, is
A. 1 : 2 : 4
B. 1 : 3 : 6
C. 1 : 1 ½ : 3
D. 1 : 1 : 2
Answer : C

40. For the construction of R.C.C. slabs, columns, beams, walls, etc. the grade of concrete mix used, is
A. 1 : 3 : 6
B. 1 : 1 ½ : 3
C. 1 : 2 : 4
D. 1 : 1 : 2
Answer : C

41. Pick up the correct statement from the following:
A. Continuous grading is not necessary for obtaining a minimum of air voids
B. The omission of a certain size of aggregate is shown by a straight horizontal line on the grading curve
C. The omission of a certain size of aggregate in concrete increases the workability but also increases the liability to segregation
D. All the above
Answer : D

42. Allowable shear strength of concrete, depends upon
A. Shear strength
B. Tensile strength
C. Compressive strength
D. None of these
Answer : A

43. Pick up the incorrect statement from the following:
A. Space between the exterior walls of a warehouse and bag piles should be 30 cm
B. Cement bags should preferably be piled on wooden planks
C. Width and height of the pile should not exceed 3 m and 2.70 m respectively
D. None of these
Answer : D

44. Internal friction between the ingredients of concrete, is decreased by using
A. Less water
B. Fine aggregates
C. Rich mix
D. More water and coarse aggregates
Answer : D

45. Permissible compressive strength of M 200 concrete grade is
A. 100 kg/cm²
B. 150 kg/cm²
C. 200 kg/cm²
D. 250 kg/cm²
Answer : C

46. Permissible compressive strength of M 150 concrete grade is
A. 100 kg/cm2
B. 150 kg/cm2
C. 200 kg/cm2
D. 250 kg/cm2
Answer : C

47. Pick up the correct statement from the following:
A. The concrete gains strength due to hydration of cement
B. The concrete does not set at freezing point
C. The strength of concrete increases with its age
D. All the above
Answer : D

48. How long will it take for the concrete to achieve 100% of its strength?
A. 7 days
B. 14 days
C. 21 days
D. 28 days
Answer : D

49. The produce impermeable concrete
A. Thorough mixing of concrete is required
B. Proper compaction of concrete is required
C. Proper curing of concrete is required
D. All the above
Answer : D

50. Workability of concrete mix with low water cement ratio is determined by
A. Tensile strength test
B. Slump test
C. Compaction factor test
D. Flexural strength test
Answer : C